<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <style>
      div {
        width: 600px;
        height: 300px;
      }
      .rainbow {
        background: radial-gradient(
          circle farthest-side at 50% 100%,
          white 40%,
          pink 50%,
          pink 55%,
          red 60%,
          red 65%,
          orange 70%,
          orange 75%,
          skyblue 80%,
          skyblue 85%,
          yellow 90%,
          yellow 95%,
          white 95%
        );
      }
    </style>
    <div class="rainbow"></div>
  </body>
</html>
